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摩托车污染控制催化转化器的试验研究 总被引:3,自引:0,他引:3
本文介绍摩托车排气净化催化转化器的研究情况,包括催化剂的研制及转化器的结构设计,经过实验室模拟尾气活性评价、转鼓台架检测、实车试验,证明所研制的催化转化器具有较好的催化活性实用性。同时讨论了催化转化器与二冲程、四种程摩托车匹配的问题。 相似文献
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车用三效催化转化器发展概况 总被引:2,自引:0,他引:2
从载体及三效催化剂角度论述了车用三效催化转化器的发展;指出了影响车用三效催化转化器性能的因素,这些因素的作用是协同的;为提高催化转化器的性能,必须采用系统的方法对其进行优化设计。 相似文献
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车用催化转化器的数值模拟与实验研究 总被引:1,自引:0,他引:1
采用数值模拟和实验相结合的方法比较了常规结构和一种特殊结构双载体三效催化转化器的性能。数值模拟的结果表明,安装环形片的催化转化器流动均匀性优于常规结构的催化转化器。实验结果表明,安装环形片可以提高催化器的转化效率。 相似文献
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本文论述了摩托车排放控制催化净化系统的应用特点 ,并在与国内摩托车生产厂家进行催化净化系统匹配的试验基础上 ,提出了应用摩托车催化净化系统可能遇到的问题和解决方案 相似文献
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《Atmospheric environment (Oxford, England : 1994)》1999,33(2):205-215
Time-Resolved Chemical Ionization Mass Spectrometry (CIMS) has been used to investigate the emission profiles of benzene, toluene and the C2-benzenes (xylenes and ethyl benzene) in automotive exhaust during transient engine operation. On-line emission measurements with a frequency of 1–5 Hz clearly identified the critical driving conditions that are mainly responsible for the overall aromatic hydrocarbon emissions. The passenger car, equipped with a catalytic converter showed significant BTXE-emissions only in the first part of the New European Driving Cycle (NEDC) due to sub-optimal catalyst temperature. On the same car without a catalytic converter, emissions of aromatic hydrocarbons were detected over the entire test run and the benzene–toluene mixing ratios of the exhaust gas were rather constant. With catalytic exhaust gas treatment the observed benzene–toluene mixing ratios varied to a greater extent reflecting predominantly different catalytic converter conditions. The average molar ratio of benzene over toluene rose from 0.33 to 0.53 upon exhaust gas treatment. With catalytic converter the emissions during extra urban (EUDC) driving repeatedly showed benzene–toluene mixing ratios >1 and an average molar benzene/toluene ratio of 0.74 was detected during the EUDC part of the driving cycle. Whereas the total hydrocarbon (T.HC) emissions were decreased by 83% upon exhaust gas treatment the overall reduction of the benzene emissions was only 70%. 相似文献
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Sara Arphorn Tomohiro Ishimaru Kunio Hara Suwisa Mahasandana 《Journal of the Air & Waste Management Association (1995)》2018,68(2):139-145
The motorcycle taxi drivers of Bangkok have been heavily exposed to high concentrations of PM10 (particulate matter with an aerodynamic diameter ≤10 μm), and the impact of this on their lungs has been neither documented nor studied. This study examines the association between exposure to PM10 and lung function decline among motorcycle taxi drivers. A cross-sectional study was conducted in Bangkok between two groups: a subject group of motorcycle taxi drivers and control group of enclosed vehicle taxi drivers. The findings of the Thailand Pollution Control Department were used to estimate the annual ambient PM10 concentration levels in the metropolis. Pulmonary functions of motorcycle taxi drivers and enclosed vehicle taxi drivers were measured and compared using the Mann-Whitney test. Multiple linear regression analysis was applied to estimate the effects of PM10 exposure on the lung function of motorcycle taxi drivers. A total of 1283 motorcycle taxi drivers and 600 taxi drivers were investigated. The mean forced expiratory volume in 1 sec/forced vital capacity (FEV1/FVC) of the motorcycle taxi drivers was significantly lower than that of the taxi drivers (P < 0.001). The mean FEV1/FVC of motorcycle taxi drivers exposed to ≥50 µg/m3 PM10 was statistically lower (?2.82%; 95% confidence interval [CI]: ?4.54% to ?1.09%) and the mean % vital capacity (%VC) of those exposed to 40–49.9 µg/m3 PM10 was statistically lower than that of motorcycle taxi drivers exposed to <30 µg/m3 PM10 (?3.33%; 95% CI: ?5.79% to ?0.87%). Motorcycle taxi drivers were directly exposed to air pollution in their working environment. As a result, their lung function might decrease more than that of enclosed vehicle taxi drivers. With the possible exposure to ≥50 µg/m3 PM10, the vehicular emission standards should be vigorously enforced. Further investigation is warranted to clarify the effect of lung dysfunction on the work and lifestyle of motorcycle taxi drivers.Implications: Motorcycle taxi drivers are directly exposed to air pollution in their work environment; therefore, their lung function might decrease more than that of enclosed vehicle taxi drivers, especially when exposed to ≥50 µg/m3 PM10. World Health Organization (WHO) vehicular emission standards should be recognized and eventually enforced. 相似文献
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Díaz L Schifter I Rodriguez R Avalos S López G López-Salinas E 《Journal of the Air & Waste Management Association (1995)》2001,51(5):725-732
A 1999 ordinance by the Government of Mexico City bans 1993 model-year vehicles from on-road operation if their catalytic converters are not replaced with new ones. To validate the benefits of this action, we examined three issues related to exhaust emissions of vehicles equipped with catalytic converters. After selecting representative fleets of in-use vehicles, a comparison between emissions and catalyst efficiency in cars with two categories of exhaust emission limits was carried out. For that purpose, two fleets were selected, each made up of 10 vehicles run under similar conditions. A third, larger fleet with emissions control systems was used to evaluate and simulate real-world conditions of vehicles in a controlled laboratory. Finally, the aging effect on the catalytic converter was studied on vehicles run for 100,000 km, replacing their old emission control devices for new ones. The 1991-1992 model-year vehicles showed a high percentage of compliance with the corresponding emissions standard (90%) in comparison with 1993 model-year and later vehicles (Tier 0). However, NOx emissions were higher for the newer vehicles. Fifty percent of the 1991-1992 model-year vehicles evaluated under the official inspection/maintenance (I/M) procedure did not meet the regulated emissions standard when the results were compared with those of the U.S. Federal Test Procedure FTP-75. Our results suggest that the replacement of old catalytic converters with new ones will have little effect on decreasing polluting emissions because these vehicles were in very bad mechanical condition. Results of catalytic activity as a function of mileage indicated inefficient catalyst performance for the fleets tested. All pollutant conversions were below 90% efficiency, and they deteriorated by an average of 30% after the vehicles were run for 100,000 km. 相似文献